two rough identical discs are rotatating in the same sense say clockwise with the same angular velocity and are brought in contact with each other
see image........
now the system is having an angular momentum 2Iw into plane............
and on this system there is no external force......so the angluar momentum of this system is constant.....but when both are brought in contact the oppose their rotation and by symmetry both will stop rotating because of the frictional torque which opposes their rotation.......
hence angular momentum of the system is destroyed without the impact of external angular impulse.
please explain.....how the law of conservation of angular momentum is broaken
note:discs are rotatating in the same sense say clockwise.
In reply to aditya ravichanndran
Re: angular momentum..........a conceptual question
by Srinath Murthy -
If the frictional torque is due to internal friction of the system alone then there should be a final nonzero common angular velocity for both and that won't break conservation of angular momentum principle. If the frictional torque is due to external friction then coservation of angular principle is not applicable.